/**
 * @file lv_math.c
 *
 */

/*********************
 *      INCLUDES
 *********************/
#include "lv_math.h"
#include <Library/minstdbool.h>

/*********************
 *      DEFINES
 *********************/

/**********************
 *      TYPEDEFS
 **********************/

/**********************
 *  STATIC PROTOTYPES
 **********************/

/**********************
 *  STATIC VARIABLES
 **********************/
static int16_t sin0_90_table[] = {
    0,     572,   1144,  1715,  2286,  2856,  3425,  3993,  4560,  5126,
    5690,  6252,  6813,  7371,  7927,  8481,  9032,  9580,  10126, 10668,
    11207, 11743, 12275, 12803, 13328, 13848, 14364, 14876, 15383, 15886,
    16383, 16876, 17364, 17846, 18323, 18794, 19260, 19720, 20173, 20621,
    21062, 21497, 21925, 22347, 22762, 23170, 23571, 23964, 24351, 24730,
    25101, 25465, 25821, 26169, 26509, 26841, 27165, 27481, 27788, 28087,
    28377, 28659, 28932, 29196, 29451, 29697, 29934, 30162, 30381, 30591,
    30791, 30982, 31163, 31335, 31498, 31650, 31794, 31927, 32051, 32165,
    32269, 32364, 32448, 32523, 32587, 32642, 32687, 32722, 32747, 32762};

/**********************
 *      MACROS
 **********************/

/**********************
 *   GLOBAL FUNCTIONS
 **********************/

/**
 * Convert a number to string
 * @param num a number
 * @param buf pointer to a `char` buffer. The result will be stored here (max 10
 * elements)
 * @return same as `buf` (just for convenience)
 */
char *lv_math_num_to_str(int32_t num, char *buf)
{
  char *buf_ori = buf;
  if (num == 0) {
    buf[0] = '0';
    buf[1] = '\0';
    return buf;
  }
  else if (num < 0) {
    (*buf) = '-';
    buf++;
    num = LV_MATH_ABS(num);
  }
  uint32_t output = 0;
  int8_t   i;

  for (i = 31; i >= 0; i--) {
    if ((output & 0xF) >= 5)
      output += 3;
    if (((output & 0xF0) >> 4) >= 5)
      output += (3 << 4);
    if (((output & 0xF00) >> 8) >= 5)
      output += (3 << 8);
    if (((output & 0xF000) >> 12) >= 5)
      output += (3 << 12);
    if (((output & 0xF0000) >> 16) >= 5)
      output += (3 << 16);
    if (((output & 0xF00000) >> 20) >= 5)
      output += (3 << 20);
    if (((output & 0xF000000) >> 24) >= 5)
      output += (3 << 24);
    if (((output & 0xF0000000) >> 28) >= 5)
      output += (3 << 28);
    output = (output << 1) | ((num >> i) & 1);
  }

  uint8_t digit;
  bool    leading_zero_ready = false;
  for (i = 28; i >= 0; i -= 4) {
    digit = ((output >> i) & 0xF) + '0';
    if (digit == '0' && leading_zero_ready == false)
      continue;

    leading_zero_ready = true;
    (*buf)             = digit;
    buf++;
  }

  (*buf) = '\0';

  return buf_ori;
}

/**
 * Return with sinus of an angle
 * @param angle
 * @return sinus of 'angle'. sin(-90) = -32767, sin(90) = 32767
 */
int16_t lv_trigo_sin(int16_t angle)
{
  int16_t ret = 0;
  angle       = angle % 360;

  if (angle < 0)
    angle = 360 + angle;

  if (angle < 90) {
    ret = sin0_90_table[angle];
  }
  else if (angle >= 90 && angle < 180) {
    angle = 179 - angle;
    ret   = sin0_90_table[angle];
  }
  else if (angle >= 180 && angle < 270) {
    angle = angle - 180;
    ret   = -sin0_90_table[angle];
  }
  else { /*angle >=270*/
    angle = 359 - angle;
    ret   = -sin0_90_table[angle];
  }

  return ret;
}

/**
 * Calculate a value of a Cubic Bezier function.
 * @param t time in range of [0..LV_BEZIER_VAL_MAX]
 * @param u0 start values in range of [0..LV_BEZIER_VAL_MAX]
 * @param u1 control value 1 values in range of [0..LV_BEZIER_VAL_MAX]
 * @param u2 control value 2 in range of [0..LV_BEZIER_VAL_MAX]
 * @param u3 end values in range of [0..LV_BEZIER_VAL_MAX]
 * @return the value calculated from the given parameters in range of
 * [0..LV_BEZIER_VAL_MAX]
 */
int32_t lv_bezier3(uint32_t t, int32_t u0, int32_t u1, int32_t u2, int32_t u3)
{
  uint32_t t_rem  = 1024 - t;
  uint32_t t_rem2 = (t_rem * t_rem) >> 10;
  uint32_t t_rem3 = (t_rem2 * t_rem) >> 10;
  uint32_t t2     = (t * t) >> 10;
  uint32_t t3     = (t2 * t) >> 10;

  uint32_t v1 = ((uint32_t)t_rem3 * u0) >> 10;
  uint32_t v2 = ((uint32_t)3 * t_rem2 * t * u1) >> 20;
  uint32_t v3 = ((uint32_t)3 * t_rem * t2 * u2) >> 20;
  uint32_t v4 = ((uint32_t)t3 * u3) >> 10;

  return v1 + v2 + v3 + v4;
}

/**********************
 *   STATIC FUNCTIONS
 **********************/
